v0.3T - Ventmon Tester 0.3

This release contains the firmware as distribute in the most recent 10 VentMons. It also contains the PCB design files and 3D printable files for that hardware configuration. The "T" in the release name stands for "Tester". Although we hope the VentMon will someday be incorporated into a pandemic response ventilator, it is not yet ready to be a life-critical medical monitoring device.